Search

Calcareous grasslands are highly biodiverse semi-natural habitats. A particular challenge to European calcareous grassland management in recent years has been the increasing dominance of the competitive grass Brachypodium pinnatum . B. pinnatum is difficult to control by traditional means but selective herbicides offer a potential alternative. We trialled five selective herbicides on two levels of B. pinnatum cover (sparse and dense) at a UK calcareous grassland site over three years of repeated treatment. We compared the effect of herbicides with a minimal intervention treatment (cutting) and current management practices (cutting and grazing for sparse cover, broad-spectrum glyphosate application for dense cover) on the cover of B. pinnatum , key indicator species and the composition of the grassland community. Areas with initially sparse B. pinnatum showed no significant reduction under any herbicide, whilst some herbicides (propyzamide, cycloxydim) showed detrimental impacts on non-target species. Cutting and grazing showed some beneficial effects, despite no significant reduction in B. pinnatum . On areas of dense B. pinnatum cover, glyphosate application reduced cover of B. pinnatum but led to colonisation by negative indicators or species typical of agricultural situations and disturbed ground. None of the selective herbicides significantly reduced dense B. pinnatum cover, and some (propyzamide, tepraloxydim, fluazifop-P-butyl) had significant negative impacts on non-target species. Our results suggest herbicide treatments, including glyphosate, are unlikely to offer long-term control of B. pinnatum on calcareous grasslands. A more promising approach is suggested by the effect of cutting and grazing, although further experimentation is required to determine the most effective regimes.

Although grasslands are crucial habitats for European butterflies, large-scale declines in quality and area have devastated many species. Grassland restoration can contribute to the recovery of butterfly populations, although there is a paucity of information on the long-term effects of management. Using eight UK data sets (9-21. years), we investigate changes in restoration success for (1) arable reversion sites, were grassland was established on bare ground using seed mixtures, and (2) grassland enhancement sites, where degraded grasslands are restored by scrub removal followed by the re-instigation of cutting/grazing. We also assessed the importance of individual butterfly traits and ecological characteristics in determining colonisation times. Consistent increases in restoration success over time were seen for arable reversion sites, with the most rapid rates of increase in restoration success seen over the first 10. years. For grasslands enhancement there were no consistent increases in restoration success over time. Butterfly colonisation times were fastest for species with widespread host plants or where host plants established well during restoration. Low mobility butterfly species took longer to colonise. We show that arable reversion is an effective tool for the management of butterfly communities. We suggest that as restoration takes time to achieve, its use as a mitigation tool against future environmental change (i.e. by decreasing isolation in fragmented landscapes) needs to take into account such time lags. © 2012 Elsevier Ltd.